Post on 17-Jan-2016
C 16- Primate Evolution
Pp. 420-441
Content
• 16-1 Primate Adaptation & Evolution
• 16-2 Human Ancestry
Primate Adaptation & Evolution
• Primates – group of mammals including lemurs, monkeys, apes & humans.
• Common traits – opposable thumbs, binocular vision, large relative brain volume, flexible arms & joints, grasping feet.
Primate Origins
• Strepsirrhines earliest fossils 50 -55 MYA
• Current ex. Lemurs, aye-ayes in Africa & SE Asia
• Typically small, nocturnal animals w/ big eyes
Primate Origins
• Haplorhines – tarsiers & anthropoids such as hominoids including apes & humans, Old & New World monkeys
• More complex brains, more upright posture, different skeletal features.
Primate Origins
• New World Monkeys- 30 -35 MY old fossils• Central & S America• Arboreal with prehensile tail
Primate Origins
• Old World Monkeys• Arboreal or terrestrial
without prehensile tails; includes colobus monkeys, macaques, baboons.
• Adapted to many varied environments from hot, dry savannas to cold mountain forests.
Fossils 20 – 22 MYA
Primate Origins
• Hominoids- apes (orangutans, gibbons, chimpanzees, bonobos, gorillas) or humans
• Lack tails, have long, muscled forelimbs, large brain capacity
• Oldest anthropoid fossils 37 – 40 MYA
Primate Origins
• By examining DNA of modern hominoids, scientists have evaluated the probable order in which apes and humans evolved.
• Chimpanzees share the closest common ancestor w/ humans.
Jane Goodall
16.2 Human Ancestry
• In Africa, 5-8 MYA, a population ancestral to chimpanzees & humans diverged.
• May have been due to environmental changes.
• Bipedal hominids had a survival advantage.
Human Ancestry
• Australopithecus africanus discovered by Raymond Dart 1924 with features of both apes & humans.
• Braincase & facial structure of ape & position of foramen magnum like humans
• 2.5-2.8 MYA
Human Ancestry
• Paleoanthropologist Donald Johanson (1974) “Lucy” Australopithecus afarensis found in E Africa 3-4 MYA
• Although braincase was more like chimp, pelvic bone was more humanlike.
The Emergence of Modern Humans
• <embed src="http://sciencestage.com/flvplayer.swf" quality="high" width="450" height="367" name="VideoPlayer" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer" FlashVars="file=http://www.youtube.com/watch?v=k-4FHl1-Jcs&width=450&height=367&displaywidth=450&displayheight=367&overstretch=true&showfsbutton=false&image=http://sciencestage.com/uploads/thumbs/40cairqx3is83z4u.jpg&link=http://sciencestage.com/v/5586/walking-with-cavemen-part-2-blood-brothers-3-of-3.html&linktarget=_blank&backcolor=0xFFFFFF" wmode="transparent" border="0"><a href="http://sciencestage.com/v/5586/walking-with-cavemen-part-2-blood-brothers-3-of-3.html">Walking with Cavemen - Part 2 Blood Brothers 3 of 3</a>></embed>
• Handy man or Homo habilis
• 1.5 -2.5 MYA
Homo habilis skull
Primate Adaptation & Evolution
• Handy man or Homo habilis
• 1.5 -2.5 MYA• Discovered 1964 by
Louis & Mary Leakey in Olduvai Gorge, Tanzania in Africa
• Earliest known hominid to use tools
Homo habilis
The Emergence of Modern Humans
• Homo erectus 1.5-1.8 MYA “upright human”
• Larger brain, more human face, prominent brow ridges, lower jaw w/ no chin
• Evidence suggests hunters lived in caves Africa, Asia, & Europe
The Emergence of Modern Humans
• H. sapiens 100,000 – 500,000 YA
• Neandertals 35,000 – 100,000YA during ice age, had religious views & spoken language
• Cro Magnon more modern with similar size to humans, toolmakers & artists
Emergence of Modern Humans
• Humans haven’t changed much in past 200,000 years.
• Africa, Europe, Asia, North America
• 10,000-8000 YA native Americans had establish settlements w/ domesticated animals & farming